One study finds little or no correlation between early formal child care and later behavioural problems while another warns of the intellectual and social dysfunctions a child might suffer if left largely in the care of strangers.

The research war has been fought at a superficial level, says Professor Frank Oberklaid, director of the Centre for Community Child Health at Melbourne's Royal Children's Hospital. And the terms of engagement have reached an ideological impasse.

"Working women are feeling overburdened with guilt and women at home are feeling smug," he says.

"The real question we should be debating is how can we provide the best care environment for children ... and support women in their choices?"

Findings in overseas and local studies over the past three years have rung alarm bells about the possible link between long hours spent in day care of arguable quality and children's subsequent inability to adapt to school. But the effect on children of bring cloistered at home in an unstimulating environment is rarely raised, Oberklaid says. "This nonsense persists, the blanket notion that all kids should be [cared for] at home for the first five years of life."

But others argue that the debate has been hijacked by left-wingers who refuse to acknowledge evidence that young children spending long hours in day-care centres - regardless of the centre's quality - are failing to develop emotionally, psychologically and intellectually.

Key to their argument are the conclusions of US studies, including one done by the National Institute of Child Health and Human Development, which released its results in 2002. These appeared to confirm those of an Australian study, which had generated a skirmish between opposing camps the same year.

Led by the University of Melbourne's Dr Kay Margetts, a senior lecturer in primary and early childhood education, the study of 212 children in 12 kindergarten classrooms at four Melbourne state primary schools made for depressing reading. Children who spent more than 30 hours a week in non-parental child care were found to be more aggressive and disobedient, and had poorer social and academic skills.

And the younger a child was when placed in a long-day care centre, the more the child was at risk of developing behavioural and intellectual problems in the first year of school. Home-based parental care, with attendance at a pre-school for older children, was clearly the optimum environment for raising bright, co-operative children.

Second best option? Get a nanny.

When the Australian Institute of Family Studies (AIFS) was invited by The Age to comment on the findings, the institute's principal researcher, Sarah Wise, signalled her suspicions. It appeared that influencing factors such as the quality of the formal care and of the home environment had not been taken into account. The number of hours spent in child care, she said, was largely irrelevant. "The only time I have ever heard of long hours in child care being harmful is where the quality of the care is poor and there is also ineffective parenting," she said.

Wise's comments attracted almost as much controversy as Margetts's study.

To dismiss the University of Melbourne's findings so lightly was evidence enough that she and the AIFS had been hijacked by what the former institute chief Peter Saunders, now with Sydney's conservative Centre for Independent Studies, described as a "broadly left-feminist agenda". When it came to a clash between hard facts and feminist ideology, the AIFS's history was replete with examples of selective and distorted findings, the Herald's Bettina Arndt argued. Perhaps the Howard Government should staff the institute's board with people who had more appropriate attitudes, it was suggested.

So lasting was the fallout from the public row that when the Herald contacted Wise this week she referred the matter on to an AIFS spokeswoman, who said the institute had decided not to comment on the University of Melbourne study, or the fracas surrounding it, ever again.

Margetts, however, said she was standing by her findings. And so disturbing are these findings that governments should either dramatically raise the ratio of carers to children in formal child-care settings or adopt a policy which will discourage parents' excessive use of formal child care for their infants and toddlers.

The animosity she has experienced from some fellow researchers, Margetts claims, stems mainly from the fact that her study pre-empted other projects on child care.

That the ongoing child-care debate is invested with so much raw emotion is hardly surprising, says Dr Margaret Sims, the co-ordinator of Children and Family Studies at Edith Cowan University, Perth. The child-care conundrum, she says, is imbued with all the passion and power associated with the inseparable notions of womanhood and motherhood. "Child care is a challenge to the standard role of women being good mothers, which is why paid maternity leave will always be politically more popular than paid child care," she says.

"Women today know they have a right to be in the public sphere, they know they have the right to work, but at the same time we're still enmeshed in a culture which gives women a guilty conscience for not looking after the kids full-time.

"So we're seeing more support to allow women to stay home but child care is seen as the selfish woman's option. And what government wants to be seen subsidising selfish women?"

Last July, the Chicago-based international journal Child Development published a report on three studies into the effects of formal child care, written by American, Israeli and Australian academics. The Australian contributor was Linda Harrison, a senior lecturer in early childhood education at Charles Sturt University. The collaborative research pointed to a correlation between poor-quality child care and behaviour problems in later life. But when the care was categorised as being of high quality young children were likely to benefit from the system.

The findings backed up comments the AIFS's Wise made the previous year. "Child care is always a secondary influence on a child's development," says Harrison. "The family environment is still more important. All the studies find that, and any research which expects to be judged internationally must take account of this."

This was evident in the Early Head Start findings, where American children from disadvantaged homes were placed in federally controlled centres with staff-child ratios of 1 to 4. All staff held a Child Development Associate credential, considered desirable but not essential for staff in US centres. Children in the Early Head Start program were less aggressive and better developed socially and emotionally at the age of three than the stay-at-home control group of children. And the more hours the Early Head Start children attended child care, which was increased incrementally with age, the more positive the results became.

However, the opposite was found in an Israeli study, so Harrison says placing overseas research into an Australian context must be done cautiously.

On a seven-point scale, Australia averages around five when it comes to consistency of the quality of care in child-care centres. In the US, the score is around three to four.

Harrison attributes our high level of formal care on Commonwealth Government regulations which provide a rigorous system of accreditation combined with a requirement for qualified staff, holding either a four-year university degree in early childhood or a two-year TAFE course in children's services.

"Australia is doing well, but that doesn't mean we can start taking it for granted," she says. "We're seeing fewer young people in these courses, and the low pay and working conditions are contributing to a downward trend."

Pediatrician Frank Oberklaid says: "There's this perception that child care is only 'child minding'. It's like being a babysitter ... working in a creche. But these people are early childhood development professionals. Language is important, not just symbolically but also at a practical policy level. Start calling a child-care centre a child development centre and you instantly change the image. And maybe that would begin to change some of our ideological starting points."